Mert YILMAZ, Alp ALTINTOP, Berk AYDOĞAN, Zerrin SERT, Çisil TİMURALP

MERKEZİNDE EĞİMLİ ELİPTİK SİLİNDİR BULUNAN KAPALI KUTULARDA ISI GEÇİŞİ

Bu çalışma, kare kapalı kutu içindeki ısıtılmış eğimli eliptik silindirin doğal taşınımla ısı geçişini inceleyebilmek için iki boyutlu sayısal olarak analiz edilmiştir. Çalışmada kare kapalı kutunun yüzeyleri soğuk, eliptik silindir ise ortamın tek ısı kaynağıdır. Analiz yapılırken eliptik silindir için üç farklı eğim açısı (θ=0°, 45°, 90°), eliptik silindirin dört farklı en/boy oranı (b/a=0.25, 0.5, 0.75, 1.0) ve dört farklı Rayleigh sayısı (Ra=104, 105, 106, 107) göz önünde bulundurulmuştur. Sistemde bulunan havanın termofiziksel özelliklerinin sabit olduğu ancak yoğunluğun Boussinesq yaklaşımı altında sıcaklıkla değiştiği ve akışkanın hareketinin yoğunluk farkından dolayı gerçekleştiği varsayılmıştır. Çözümlerden elde edilen veriler doğrultusunda eliptik silindir üzerinden hesaplanmış ortalama Nusselt sayısı grafiklerde verilmiştir. Ayrıca eş sıcaklık eğrileri ve akım çizgileri de sunulmuştur.

Anahtar Kelimeler:

Doğal taşınım, Eğimli eliptik silindir

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